Objective: To describe the proper statistical approach in ophthalmic research for analyzing correlated data for contralateral eyes of the same subjects. Methods: For data from a paired design and a design for two eyes that are commonly used in ophthalmic research, we described the appropriate statistical approaches for analyzing the correlated data for both eyes of the same subjects. As an example, we compared the intraocular pressure between patients < 60 vs. ≥ 60 years of age, using the inappropriate and appropriate statistical analysis approaches. Results: The inappropriate analysis of data for one eye leaded only to a biased or inefficient estimate of the difference between two groups. The analysis of data for both eyes of the same subjects without accounting for inter-eye correlation had a smaller p-value (P=0.02) than the analysis that accounted for inter-eye correlation (P=0.098). Conclusions: Appropriate statistical analytical approaches should be used to account for the inter-eye correlation. The statistical analysis using data for only one eye or ignoring the inter-eye correlation can lead to an incorrect conclusion.

Objective: To evaluate the efficacy of the multimedia visual perceptual learning system for improving visual acuity in pediatric patients with amblyopia and to discuss factors influencing the therapeutic effects of perceptual learning. Methods: This was a prospective randomized controlled study. Amblyopic children aged from 3 to 11 years (n=112) were recruited from the ophthalmology clinic. Participants were randomly assigned to the experimental group that utilized the multimedia visual perceptual learning system or a control group utilizing the synoptophore. All subjects underwent perceptual learning and patching or refractive correction, depending upon the individual situation. After the baseline visit, follow-up visits were held after 10, 20, and 30 treatments. Finally, the clinical efficacy and improvement of visual acuity in the two groups were analyzed and compared, using chi-square test, independent-samples t test, Pearson correlation test. Results: The curative effect of the experimental group was better than the control group at different training periods (Z=-4.128, -4.806, -3.063, P<0.001). The change in visual acuity in the experimental group was significantly higher at the 10th and 20th training sessions (t=3.471, 3.290, P<0.05).In the moderate and severe amblyopia groups, the curative effect of the experimental group was better than the control group (Z=-3.050, P=0.021), and was the same as in the anisometropic amblyopia group
(Z=-2.864, P=0.004) and 7-11 year-old group (Z=-2.631, P=0.009). There was a moderate correlation at baseline and an improvement in visual acuity in both groups (r=0.690, 0.650, P<0.05). Conclusions: The multimedia visual perceptual learning system can achieve an optimal effect in a short period of time. The improvement in vision relates to the sex of the patient, and the degree and type of amblyopia, which are clinically significant to amblyopia therapy.

Objective: To compare the efficacy of two methods of psychological treatment of hysterical visual impairment. Methods: Patients with hysterical visual impairment were prospective divided into an observation group (20 cases) and a control group (12 cases). The observation group was treated by wearing of plano glasses, and the control group was treated by stimulation of the temporal skin with lacrimal dilator.The curative effects and complications of the two groups were compared by using t test and chi-square test.Results: The visual acuity of the control group increased 0.78±0.21 (t=18.32, P<0.001 compared to the pretreatment value). The visual acuity of the observation group increased by 0.82±0.21 (t=24.84, P<0.001 compared to the pretreatment value). The difference of increasement in visudal actity between the two groups was not statistically significant (t=0.75, P=0.45). The improvement rate of visual field was 83%in the control group and 89% in the observation group, there was no significant difference between the two groups (χ2=1.50, P=0.30). Two cases in the control group with complications (skin trauma), and none occurred in the observation group (χ2=11.89, P=0.002). Conclusions: Treatment of hysterical vision by spectacle wearing and by skin stimulation similarly improved visual acuity. While skin stimulation caused some complications, there were no adverse reactions to wearing glasses.

Objective: To analyze the health-related quality of life (HRQOL) in adults with strabismus, and to identify the factors that affect the HRQOL in strabismus patients. Methods: In this investigation study, 202 adults with strabismus and 110 healthy control adults were recruited. Participants were asked to complete the Chinese Adult Strabismus 20 scale (CAS-20) HRQOL assessment. The following individual information was recorded: type and degree of strabismus, diplopia, age, sex, and marital status. Independent samplest-tests, ANOVA, Pearson correlation analyses, multiple linear regression analyses were used to analyze the effects of strabismus on HRQOL in adults based on the CAS-20 score. Results: The mean CAS-20 score for strabismus adults was 56.8±16.7, while the score in the control group was 98.0±4.3 (t=-35.2,P<0.001). The CAS-20 function score of patients with diplopia was significantly lower than that for patients without it (t=-1.987, P=0.047). The CAS-20 mean scores were all significantly lower in patients with amblyopia (t=-2.122, P=0.004). The psychosocial score of patients with a large horizontal strabismus(>25△) was significantly lower than those with a small horizontal strabismus (≤25△) (t=2.523, P=0.007).There were no significant differences among the different types of strabismus. Age and the course of strabismus were negatively correlated with the HRQOL in strabismus adults (r=-0.260, P < 0.001; r=
-0.142, P=0.035). Married strabismus subjects had lower scores than unmarried subjects (t=2.981, P=0.004). Patients who were students had higher scores (t=-2.084, P=0.038). A multifactor retrospective analysis showed that age and the course of the strabismus, with or without amblyopia, were the main factors affecting the HRQOL for strabismic adults. Conclusions: The HRQOL of adults with strabismus is worse than that for healthy adults. The CAS-20 function scores of patients with diplopia or amblyopia are significantly lower than for patients without diplopia or amblyopia. The course of strabismus, age and with or without amblyopia are important factors in HRQOL.

Objective: To use Fourier analysis to evaluate the accuracy of myopic astigmatism correction in femtosecond laser in situ keratomileusis (FS-LASIK) and transepithelial photorefractive keratectomy(TPRK). Methods: A total of 267 myopic astigmatism patients (453 eyes) were included in this retrospective case group study. Patients were treated with either FS-LASIK (n=137, 228 eyes) or TPRK (n=130,225 eyes) at the Eye Hospital of Wenzhou Medical University from June, 2015 to June, 2016. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction, and corneal topography were measured preoperatively and postoperatively at 3 to 6 months. Fourier analysis was used to transform the preoperative astigmatism to TJ0 and TJ45, the preoperative corneal astigmatism to CJ0 and CJ45, the postoperative residual astigmatism to RJ0 and RJ45, and the astigmatism correction rate to CRJ0 and CRJ45.Covariance rank sum test, Mann-Whitney U test, and Wilcoxon signed rank sum test were used for statistical analyses. Results: For the FS-LASIK group, TJ0=0.369 D, TJ45=-0.043 D, CJ0=0.695 D, CJ45=-0.018 D,RJ0=0.000 D, RJ45=0.000 D, CRJ0=100%, CRJ45=100%. For the TPRK group, TJ0=0.369 D, TJ45=0.000 D,CJ0=0.600 D, CJ45=0.003 D,RJ0=0.000 D, RJ45=0.000 D, CRJ0=100%, CRJ45=100%. Comparing betweenFS-LASIK and TPRK, the values for TJ0, TJ45, CJ45, RJ45, CRJ45 were not statistically significant (P>0.05).CJ0 and RJ0 in the FS-LASIK group were higher than in the TPRK group (Z=-2.615, P=0.009; Z=-2.419,P=0.016). CRJ0 in the TPRK group was significantly higher than in the FS-LASIK group (Z=-1.978,P=0.048). For intra-group comparisons, TJ0 and CJ0 were statistically higher than TJ45 and CJ45 in the FSLASIK group (Z=-10.886, -12.926, both P<0.001). RJ0 and RJ45, and CRJ0 and CRJ45 were not significantly different. TJ0 and CJ0 were statistically higher than TJ45 and CJ45 in the TPRK group (Z=-10.539, -12.735, both P<0.001). RJ0 and RJ45, and CRJ0 and CRJ45 were not significantly different. Conclusions: Both FS-LASIK and TPRK have high accuracy in the correction of cartesian astigmatism and oblique astigmatism.

Objective: To compare the changes in asymmetric indexes and asphericity of the anterior corneal surface of patients with myopia and astigmatism six months after small incision lenticule extraction (SMILE) and sub-Bowman's keratomileusis (SBK). Methods: This was a prospective, non-randomized, controlled study.
Patients underwent SMILE (96 eyes, SMILE group) or SBK (96 eyes, SBK group). The anterior corneal surface asphericity indexes and asphericity (Q-value) at a diameter of 6 mm were measured with the Pentacam before surgery and 10 days, 1 month, 3 months, and 6 months after surgery. Data were analyzed with t-tests,
repeated measures analysis of variance, and Pearson correlation analysis. Results: The removed corneal tissue in the SMILE group was significantly thicker than that in the SBK group (t=-6.717, P <0.001). There were no differences in the Q-value, or mean of keratoconus index (Km) and minimum ridius (Rmin) values. The
postoperative 1 month, 3 months, 6 months, values of the index of surface variance (ISV) were significantly larger than those in the SBK group (t=-2.168, -2.030, -2.628, all P <0.05). The postoperative values index of vertical asymmetry (IVA), index of height asymmetry (IHA), index of height decentration (IHD), and keratoconus index (KI) in the SMILE group were significantly larger than those in the SBK group (all P <0.01).For center keratoconus index (CKI) values, the outcomes in the SMILE group were lower than in the SBK group at 10 days, 1 month and 3 months (t=6.715, 5.003, 2.810, all P <0.01). There was a significant negative linear correlation between the △Q and the spherical equivalent (SE) in the two groups (SMILE: r=-0.750,P <0.001; SBK: r=-0.886, P <0.001). Conclusions: There is no difference between the Q-values in the SMILE and SBK groups. The negative linear correlation between △Q and SE is significant, and the postoperative values of ISV, IVA, IHA, IHD and KI in the SMILE group are greater than those in the SBK group.

Objective: To evaluate the correlation between new inflammatory factor interleukin-17 (IL-17) and diabetic retinopathy (DR). Methods: In this case control study, patients (n=625) with type 2 diabetes were divided into a DR group (n=251, 40.2%) and a non-diabetic retinopathy (NDR) group (n=374, 59.8%). The general information and biochemical indexes were compared between the two groups. Comparison between groups using t/χ2 square test, and the risk factors of DR were analyzed by multiple logistic regression.Results: Compared with the NDR group, the age (t=3.012), duration of diabetes (t=3.873), arteriosclerosis rate (x2=23.791), fasting blood-glucose (t=2.659), albumin/creatinine (A/C) (t=5.917), and serum IL-17 level (t=5.242) of the DR group were significantly increased (P<0.05). The sex, body mass index (BMI),hypertension, smoking, diastolic blood pressure, systolic blood pressure, glycosylated hemoglobin, total cholesterol, triglyceride, and high-density lipoprotein of the two groups were not significantly different from one another. Logistic regression analysis showed that the duration of diabetes (OR=1.120, P=0.003),A/C value (OR=1.014, P=0.028), and IL-17 (OR=0.854, P=0.002) were risk factors of DR. Conclusions:IL-17 is closely related to DR, and the level of serum IL-17 can provide significant guidance with respect to the clinical diagnosis and treatment of this disease.

Objective: To evaluate the differential diagnosis between subclinical keratoconus and simple high myopic astigmatism by using a Pentacam anterior segment analyzer. Methods: Fifty eyes of 46 patients with subclinical keratoconus (Rabinowitz diagnosis standard) and 76 eyes of 52 patients with simple high myopic astigmatism (>2.5 diopter) were included in this retrospective case control study. A Pentacam was used to measure the anterior and posterior corneal elevation parameters, minimum pachymetry (MinPachy),the index of vertical asymmetry (IVA), the index of highest decentration (IHD), the average corneal thickness progression index, and the Belin D value of the Belin/Ambrosio Enhanced Ectasia Display. An independent samples t-test was used to analyze the differences between the two groups. Receiver operating characteristic (ROC) curves were used to screen the useful parameters and determine the best diagnosis point. Results: There were significant differences between the two groups for the anterior corneal elevation parameters (t=6.77, P<0.001), posterior corneal elevation parameters (t=9.00, P<0.001), MinPachy (t=3.12,P=0.002), IVA (t=8.35, P<0.001), IHD (t=8.94, P<0.001), the average corneal thickness progression indexes (t=5.59, P<0.001), and the D values of the Belin/Ambrosio Enhanced Ectasia Display (t=13.01, P<0.001). The posterior corneal elevation parameter and the D value of the Belin/Ambrosio Enhanced Ectasia Display had the highest relevance in the differential diagnosis between subclinical keratoconus and simple high myopic astigmatism (area under the ROC curve ≥ 0.9). Conclusion: Analyzing the corneal indexes of high myopic astigmatism contributes to the screening of subclinical keratoconus.

The rhesus monkey is a primate and has been widely used in the medical research field because its morphological anatomy and physiological functions are similar to humans. An extensive literature search was done in order to further understand the morphological, structural and anatomical differences between human
and rhesus monkey eyes. Based on the extensive literature search, this paper expounds on the similarities and differences between rhesus monkey and human eyes from the perspectives of the cornea, lens,retina, sclera, refractive parameters and intraocular pressure. The aim of this study is to provide a reference for research on the rhesus monkey as an experimental animal model for human visual system diseases.